ACCURACY OF CORRECTION OF COMPLEX LOWER-EXTREMITY DEFORMITIES BY THE ILIZAROV METHOD

Gradual mechanical distraction with the Ilizarov external fixator was used on 28 limbs in 23 patients to correct complex lower-extremity def ormities of diverse causes. To determine the accuracy of realignment a nd deformity correction, the charts and radiographs were reviewed retr ospectively. Preoperative long-standing anteroposterior radiographs of the entire lower extremity were compared with those obtained at the m ost recent follow-up visit. The parameters used to assess accuracy of correction were joint alignment and joint orientation. Alignment was d etermined by mechanical axis deviation (MAD) and mechanical tibiofemor al angle (mTFA). The preoperative MAD averaged 48 mm and the postopera tive MAD 8.6 mm. The preoperative mTFA averaged 16 degrees and the pos toperative mTFA 3 degrees. The result of deformity correction from ear ly cases was compared with the result obtained from recent cases. Resi dual MAD averaged 13.2 mm in the early group and 6.4 mm in the recent group. Residual mTFA averaged 4.7 degrees in the early group and 2.2 d egrees in the recent group. Gradual correction by dynamic external fix ation can restore alignment and correct complex deformities with great accuracy. These results suggest the accuracy of correction increases with surgical experience.